1. Field of the Invention
The present invention relates to a separation/extraction apparatus for separating sheets of paper or paper-like medium from a pile of sheets of the medium in which sheets of paper or paper-like medium are stacked on a one-by-one basis, and extracting the separated sheet of paper or paper-like medium.
2. Description of the Related Art
In an apparatus for inspecting and processing sheets of paper (also called paper-like medium) such as a printer, copying machine, automated teller machine (ATM), banknote processing machine, mail processing machine, and the like, sheets of paper or paper-like medium such as printing paper, banknotes, copying paper, sealed letters, postcards, cards, securities, and the like are handled. However, it is necessary to extract a sheet of paper or paper-like medium one by one from a pile of sheets in which the sheets are stacked. Accordingly, the inspection/processing apparatus is provided with a separation/extraction apparatus for separating sheets of paper from a pile of sheets of the medium in which sheets of paper are stacked one on top of the other on a one-by-one basis, and extracting the separated sheets of paper or paper-like medium.
Heretofore, in a separation/extraction apparatus for separating sheets of paper (paper-like medium) from a pile of sheets of the medium in which sheets of paper are stacked one on top of the other, it is necessary to extract sheets of paper into the apparatus with good accuracy, and without causing any duplicate extraction. However, in the pile of sheets of the medium, the sheets of paper are in a state where the sheets of paper are in close contact with each other for a long time, and the sheets of paper adhere to each other in many cases. Thus, it is difficult to securely separate the sheets of paper from the pile of sheets of the medium one by one.
Thus, as disclosed in JP-A 2007-145567 (Kokai), a separation/extraction apparatus is proposed in which a vibrator is brought into contact with a top surface of the pile of sheets of the medium in a spot-like form to vibrate the sheets of paper or paper-like medium, thereby lowering the adhesion force between the sheets of paper in advance.
According to the separation/extraction apparatus disclosed in JP-A 2007-145567 (Kokai), it is possible to reduce the adhesion force between the sheets of paper or paper-like medium in the stacked state in advance, sufficiently suppress the frictional force between the uppermost sheets of paper and the sheets of paper stacked, extract only the uppermost sheets of paper one after another, and prevent duplicate extraction of the sheets of paper from occurring. However, when the stiffness of the sheets of paper is small (soft and feeble), the friction reducing effect by the ultrasonic vibration is liable to be reduced. Further, as for separation of an electrostatically charged sheets of paper stack, there is a problem that it is difficult to separate sheets of paper from the stack only by the ultrasonic vibration.
As described above, in the conventional separation/extraction apparatus, it is not possible to realize all-round handling for sheets of paper in various states, and development of a separation/extraction apparatus capable of giving an undoing effect to sheets of paper in all states is demanded.